Inclusive V production cross sections from 920 GeV fixed target proton-nucleus collisions

Abstract

Inclusive differential cross sections dσ pA /dx F and dσ pA /dp 2 t for the production of K 0 S , Λ, andΛ particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to √ s = 41.6 GeV in the proton-nucleon system. The ratios of differential cross sections dσ pA (K 0 S )/dσ pA (Λ) and dσ pA (Λ)/dσ pA (Λ) are measured to be 6.2 ± 0.5 and 0.66 ± 0.07, respectively, for x F ≈ −0.06. No significant dependence upon the target material is observed. Within errors, the slopes of the transverse momentum distributions dσ pA /dp 2 t also show no significant dependence upon the target material. The dependence of the extrapolated total cross sections σ pA on the atomic mass A of the target material is discussed, and the deduced cross sections per nucleon σ pN are compared with results obtained at other energies.